Re: [RFC] O(1) proc_pid_readdir

Ingo Molnar (mingo@elte.hu)
Mon, 17 Mar 2003 07:22:15 +0100 (CET)


On Sun, 16 Mar 2003, William Lee Irwin III wrote:

> I'm heavily on the side of deterministic bounds here (these things trip
> the NMI oopser, so if the bounds aren't deterministic, neither is
> stability), so I favor manfred's proc_pid_readdir() algorithm.

no, the code in question here is worst-case O(nr_tasks). It is worst-case
quadratic only if the number of syscalls done during a full 'ps' readdir()
sequence is considered as well. This thing will never trigger the NMI
oopser. And in the common-case it has constant overhead.

Ingo

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